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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#607469#8939. PermutationUESTC_NLNS#RE 0ms0kbC++141.0kb2024-10-03 14:59:362024-10-03 14:59:39

Judging History

This is the latest submission verdict.

  • [2024-10-03 14:59:39]
  • Judged
  • Verdict: RE
  • Time: 0ms
  • Memory: 0kb
  • [2024-10-03 14:59:36]
  • Submitted

answer

#include<bits/stdc++.h>
#define ll long long
using namespace std;
unordered_map<ll,int> mp;
const int N=1e6+5;
void answer(int x)
{
	printf("! %d\n",x);
	fflush(stdout);
	return;
}
int pp,n;
int query(int l,int r)
{
	if(l>=r)assert(0);
	if(mp.find(1ll*r*N+l)!=mp.end()) return mp[1ll*r*N+l];
	int x;
	printf("? %d %d\n",l,r);
	pp+=r-l+1;
	assert(pp<=3*n);
	fflush(stdout);
	scanf("%d",&x);
	mp[1ll*r*N+l]=x;
	return x;
}
void solve(int l,int r)
{
	if(l==r)
	{
		answer(l);
		return;
	}
	int mid=(l+r)/2,lmid,x=query(l,r),y;
	if(l+1==r)
	{
		if(x==l) answer(r);
		else answer(l);
		return;
	}
	if(x<=mid)
	{
		lmid=(r-l)*3.0/5+l;
		if(lmid==r) lmid--;
		y=query(l,lmid);
		if(x==y) solve(l,lmid);
		else solve(lmid+1,r);
	}
	else
	{
		lmid=(r-l)*2.0/5+l;
		if(lmid==l) lmid++;
		y=query(lmid,r);
		if(x==y) solve(lmid,r);
		else solve(l,lmid-1);
	}
	return;
}
int T;
int main()
{
	scanf("%d",&T);
	while(T--)
	{
		scanf("%d",&n);
		solve(1,n);
		mp.clear();
	}
	return 0;
}

Details

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Test #1:

score: 0
Runtime Error

input:

3
5
3
2
5
6
6

output:

? 1 5
? 1 3
? 4 5
! 4
? 1 6

result: